KS3 · English

Colons and semi-colons in analytical writing

Try this: stick two whole sentences together with nothing but a comma. It looks fine. It feels fine. And it's wrong. Let's find out why, and what to use instead.

English · Joining main clauses

Glued properly, or about to come apart?

Is the join done properly? If it is, which kind of join is it?

Still to sort

Semicolon (0)

Two connected main clauses, joined by a semicolon alone.

Where the line is: No joining word needed. The semicolon does the job a conjunction would do.

Joining word (conjunction) (0)

A coordinating conjunction such as 'and' or 'but' sits between the two main clauses.

Where the line is: The comma goes before the conjunction. With 'and', that comma is not always necessary.

Comma splice (incorrect) (0)

Two main clauses with nothing but a comma between them.

Where the line is: If a comma is the only thing between the two clauses, it's a splice.

7 of 7 still to sort.

Every sentence here joins two main clauses. Pick a sentence, then pick the box you think it belongs in. You'll see the reason straight away.

Watch out: A missing comma before 'and' is not the problem in this lesson. The problem is a comma trying to do a job it can't do on its own.

English · Joining main clauses

Which of these sounds like you?

Two main clauses need joining into one sentence.

Which is closest to what you think right now?

A comma on its own is strong enough to join them.There has to be a comma before 'and', every single time.A semicolon can't join them unless a word like 'and' comes after it.Use a semicolon, or a comma plus a joining word. A comma alone won't do.

How sure are you?

I'm sureI think soI'm guessing

A comma on its own is strong enough to join them.

This is a common misconception

Easy mistake, because commas do separate things inside a sentence. But a comma alone between two main clauses is grammatically incorrect, and the error has a name: a comma splice. Swap the comma for a semicolon, or keep it and add a joining word after it.

There has to be a comma before 'and', every single time.

This is a common misconception

This one is half right, which is why it sticks. A comma is needed before a coordinating conjunction that joins two main clauses, but with 'and' it is not always necessary. 'Mia plays the drums and her brother plays the guitar' is acceptable as it stands.

A semicolon can't join them unless a word like 'and' comes after it.

This is a common misconception

A semicolon doesn't need any help. It can join two main clauses without a coordinating conjunction, acting like a conjunction itself, as long as the two clauses express connected ideas.

Use a semicolon, or a comma plus a joining word. A comma alone won't do.

This matches the evidence

Right. Those are the two correct routes, and a comma alone is the one that fails. (And with 'and', that comma isn't always necessary.)

Comma alone: splice. Semicolon: joins connected ideas by itself. Comma plus conjunction: joins too, though with 'and' the comma is not always necessary.

Colon or dash?

Colon ( : )vsDash ( – )

They look alike from a distance and they overlap. Here's where they part company.

Focus

Adding emphasis

Colon ( : )

Can add emphasis to a word or phrase

Dash ( – )

Can add emphasis

The insight

Both can do this, so emphasis alone can't tell you which mark to pick.

Main jobs

Colon ( : )

Connects main clauses, or introduces an explanation, a quotation or a list

Dash ( – )

Marks a pause, an interruption or an abrupt change of thought

Swapping

Colon ( : )

Can be replaced by a dash

Dash ( – )

Can replace brackets or colons

In action

Colon ( : )

He had one rule: always check twice.

Dash ( – )

My brother – who never tidies anything – cleaned his room.

Predict, then check

Start with: Lena stayed calm. Now add 'although the door was locked', at the start, in the middle or at the end.

Whichever place you put 'although the door was locked', what happens to the sentence type?

English Lit · Paragraph craft

Build an analytical paragraph, slot by slot

Every sentence in a good analytical paragraph has a job. Tap a slot to see its job, then see it done.

Invented two-line extract: 'She opened the letter – and froze. Nothing moved.'

Tap a slot to fill or empty it.

Selected slot

Tap a slot above

Watch out: Your reader can't read your mind. If you skip the 'how I got there' sentence, they won't automatically follow your train of thought.

WHAT YOU'VE LEARNED

A quick recap of today's lesson.

Find the main clauses first. Then pick the join that does the job, and the effect you want.

What you need to know

A simple sentence has one main clause. A complex sentence has one main clause plus at least one subordinate clause.
A compound sentence is two main clauses joined by a coordinating conjunction or a semicolon.
Have a goZara insists 'The rain stopped and the sun came out' is a simple sentence because it's short. Is she right?
No. It's compound: two main clauses joined by 'and'.
Sentence type depends on how many main clauses there are, not how long the sentence is.
A semicolon can join two main clauses without a conjunction when the clauses express connected ideas.
A comma goes before a coordinating conjunction joining two main clauses, though with 'and' it's not always necessary.
Have a go'We packed the car and we set off.' Does it break a rule by having no comma before 'and'?
No. With 'and', the comma is not always necessary.
The comma rule for a coordinating conjunction has an exception for 'and', so a missing comma there isn't an error.
A comma alone between two main clauses is a comma splice, which is grammatically incorrect.
A colon can connect main clauses, add emphasis to a word or phrase, or introduce an explanation, quotation or list.
A dash can mark a pause, emphasis, an interruption or an abrupt change of thought, and can replace brackets or colons.
Have a goYour sentence suddenly changes direction halfway through. Colon or dash?
A dash.
A dash marks an abrupt change of thought. A colon connects or introduces instead.
A subordinate clause can go at the beginning, middle or end, and sentence type affects how a reader responds.
Good analytical paragraphs start with a clear topic sentence, a range of evidence, and the method the writer uses.
Link ideas with discourse markers, comment on specific language devices, and explain how you reached your idea.

The big picture

A comma on its own can't join two main clauses (that's a comma splice), but a semicolon can, and so can a comma plus a joining word. You'll also meet what colons and dashes each do, how sentence type and clause position shape a reader's response, and how to build an analytical paragraph that explains how you reached your idea.

Key points

1Find the main clauses first. Then decide which join does the job and gives the effect you want.

2Two main clauses can be joined by a semicolon, or by a comma plus a coordinating conjunction. A comma alone is a comma splice.

3Commas separate words, clauses or ideas within a sentence, and the way writers use punctuation can change how we see a text or a character's emotions.

4A colon connects main clauses, adds emphasis, or introduces an explanation, quotation or list. A dash marks a pause, interruption or abrupt change of thought.

5An analytical paragraph needs a topic sentence, a range of evidence, the method, comment on specific effects, linking words, and an explanation of how you reached your idea.

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Worked example

Problem

Fix this sentence: 'The sky darkened, the first drops began to fall.'

⚠ Watch out

Using a comma alone to join two main clauses (a comma splice), and believing a comma must always go before 'and'. With 'and', that comma is not always necessary.

🧠

Memory hook

A comma separates. It can't glue. To join two main clauses, bring a semicolon, or bring a comma and a joining word.

✓

Check yourself

Look at 'The tea went cold, nobody noticed.' Name the mistake, then give two different ways to fix it.

Flashcards

(14)

What is a simple sentence?

A sentence with one main clause.

What is a compound sentence?

Two main clauses joined with a coordinating conjunction or a semicolon.

What is a complex sentence?

One main clause and at least one subordinate clause.

What is a comma splice?

Two main clauses joined by only a comma. It is grammatically incorrect.

Two connected main clauses, no conjunction. Which mark can join them?

A semicolon, which acts like a conjunction when the ideas are connected.

Comma before a coordinating conjunction that joins two main clauses?

A comma is needed, although with 'and' it is not always necessary.

Name three jobs a colon can do.

Connect main clauses, add emphasis to a word or phrase, and introduce an explanation, a quotation or a list.

What can a dash do?

Mark a pause, added emphasis, an interruption or an abrupt change of thought. It can replace brackets or colons.

What do commas do?

Separate words, clauses or ideas within a sentence.

Where can a subordinate clause go in a sentence?

At the beginning, in the middle or at the end.

Why does a writer's choice of sentence type matter?

It can change the way a reader responds to the writing.

What does a good analytical paragraph include?

A clear topic sentence, a range of evidence, the method the writer uses, and comment on the effects of specific language devices.

What do discourse markers do?

Link ideas together so a paragraph is cohesive.

Why explain how you reached your idea?

The reader will not automatically be able to follow your train of thought.

Tap any card to flip it, or use Study as deck to go through them one at a time. In the full lesson these run as a spaced-repetition deck — you rate each card Hard, Good or Easy and the tricky ones keep coming back until they stick.

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Glued properly, or about to come apart?

Which of these sounds like you?

Build an analytical paragraph, slot by slot

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